power transformer calculations!

[jrsexpress]

email mo ko antonio.tecson@kentech.ie bibigyan kita ng spreadsheets...

sir please check your email thanks...

[liothecat]

mga sirs/madams baka pwede pa-share pw nyo dito sw neto..tnx

[Monde]

yung current rating b ng mga transformer ba eh yun yung current na inilalabas, kapag nag step down?,

[pintac]

Yang rating po ng transformer ay in terms of VA, lagi pong Primary VA is equal to Secondary VA kung walang sira ang winding ng Transformer, meaning po kung ano ang Apparent Power na pumasok ito rin dapat ang Apparent Power na lalabas, ang Voltage at Current po ay syempre hindi parehas, dahil ang either step-down or step-up ang Secondary, pero dapat mag-equate ang VA nito.

VA (primary) = VA (secondary)

Sampol:

Transformer VA rating = 500VA

V(primary) = 220V

V(secondary) = 24V


I(primary) = 500VA / 220V = 2.27A

I(secondary) = 500VA / 24V = 20.83A

Ang current limit ng Transformer ay depende sa VA rating nito at malalaman ito either sa Primary Current na papasok or Secondary Current na lalabas.

[tony]

Yang rating po ng transformer ay in terms of VA, lagi pong Primary VA is equal to Secondary VA kung walang sira ang winding ng Transformer, meaning po kung ano ang Apparent Power na pumasok ito rin dapat ang Apparent Power na lalabas, ang Voltage at Current po ay syempre hindi parehas, dahil ang either step-down or step-up ang Secondary, pero dapat mag-equate ang VA nito.

VA (primary) = VA (secondary)

Sampol:

Transformer VA rating = 500VA

V(primary) = 220V

V(secondary) = 24V


I(primary) = 500VA / 220V = 2.27A

I(secondary) = 500VA / 24V = 20.83A

Ang current limit ng Transformer ay depende sa VA rating nito at malalaman ito either in Primary Current or Secondary Current.

this is true in the case of an "ideal" transformer.......the "practical" transformer will have "no load" losses(core and magnetizing current losses) and copper losses, owing to copper wire's finite resistance.....

the Radiotron Designer's Handbook rev4. chapter 5 discusses transformer theory and design in details, you can look at it if you want a deeper understanding of how a practical transformer work.

[pintac]

Ang ginagawa ko para makuha ang Internal Losses o Effeciency ng transfomer ay lagyan ito ng LOAD and tabulate @ 10%, 20%, 30%, 40%, 50% up to 120% LOAD measure primary versus secondary VA tapos plot ito sa graph saka ko siya gagamitin. Kung minsan babad ko ito sa isang critical load tapos monitor ang temperature nito versus time para sigurado na hindi ito magiging heater sa loob ng casing.

[tony]

if you look here: http://www.antekinc.com/pdf/AN-5412.pdf

you can see the tests done on the transformer......

[iyo karpo]

para sa mga contractor at electrical suppliers:

http://www.delta.xfo.com/en/content/produits/Produits_configurateur.aspx

http://www.rexmanufacturing.com/calculator.html

http://www.bemag.ca/en/constructeur.aspx

[aldwin]

sino pong may copy ng calculator..paki upload uli pls..

[panyero]

pa subcribe nga po interesting..

[Johannah Aleksandria]

Hi

Meron ako dito transformer Calculator, tables para sa wire conversion etc.. Lagi ko sya gamit every time gumagawa ako transformer..
Let me know kung gusto nyo copy.. upload ko sya.. 

Prang sobra ang no. of turns sa calculator na ito.

[aldwin]

up ko lang po...

[tony]

Prang sobra ang no. of turns sa calculator na ito.

conservative ang formula nya...

para sa deeco cores ito ang gamit kong formula, Np=1750/A, kung saan yung Np ay primary turns at 220volts 60hz., A ay core area in inches....

ang computed turns at wire size na binigay ng traffo calculator ay preliminary lang, kailangan ulit-ulitin ang computation para matiyak na kakasya sa window...

i use only 80% of available window....

then of the available window, i assign 50% for primary coil and 50% for secondary coils..

designing traffo requires to do paulit ulit na kwentahan to make sure kakasya sa wndow yung built-up cores..

a wire table will serve you well...

[dj_mooo]

sis pwdng p calculate ulit ng trahsfo?

amp:20
primary V:220
secondary 55-0-55

tnx po!

[maldihtah13]

Use the calculator above with some extra turns.

[tony]

sis pwdng p calculate ulit ng trahsfo?

amp:20
primary V:220
secondary 55-0-55

tnx po!

as requested:

secondary VA= 110 x 20 = 2200
primary VA = 2200/0,7 = 3142
@220volts primary current = 14.3 amps
required core area = sqroot[3142]/5.58 = 10square inches
so a core made up of 2inch center leg stacked to 5.5 inches is required
primary turns = 1750/10 = 175 turns
a #14 can be used
secondary turns = 88 turns, use a @ #10 wire..
a 2inch core has a 1 x 3inch window, now you can double check that the coils will fit.
kung hindi kakasya, downsize mo yung wires....

material take off:
core EI-200, core weight = 5.5 x 2.94 = 16.17 kilos
copper:
mean length per turn = 15inches
length of primary coil = [175 x 15]/12 = 218.75 ft.
weight of primary coil = 218.75/80.44 = 2.719lbs or 1.23kgs.
length of secondary coils =[88 x 15]/12 = 110ft.
weight of secondary coils = 110/34.92 = 3.15 kg.

cost:

core material, 16.17kg x 110 = 1,778.7 pesos
copper, 4.38 x 700 = 3066 pesos
labor, set-up charges = 1500 pesos

total cost = 6,344.7

still lower if you are to buy a torroid of the same capacity...

[jacks]

Pwede ng pangwelding.

[dj_mooo]

as requested:

secondary VA= 110 x 20 = 2200
primary VA = 2200/0,7 = 3142
@220volts primary current = 14.3 amps
required core area = sqroot[3142]/5.58 = 10square inches
so a core made up of 2inch center leg stacked to 5.5 inches is required
primary turns = 1750/10 = 175 turns
a #14 can be used
secondary turns = 88 turns, use a @ #10 wire..
a 2inch core has a 1 x 3inch window, now you can double check that the coils will fit.
kung hindi kakasya, downsize mo yung wires....

material take off:
core EI-200, core weight = 5.5 x 2.94 = 16.17 kilos
copper:
mean length per turn = 15inches
length of primary coil = [175 x 15]/12 = 218.75 ft.
weight of primary coil = 218.75/80.44 = 2.719lbs or 1.23kgs.
length of secondary coils =[88 x 15]/12 = 110ft.
weight of secondary coils = 110/34.92 = 3.15 kg.

cost:

core material, 16.17kg x 110 = 1,778.7 pesos
copper, 4.38 x 700 = 3066 pesos
labor, set-up charges = 1500 pesos

total cost = 6,344.7

still lower if you are to buy a torroid of the same capacity...

sis salamat po!sobra2 ung info n binigay m!tnxxx

[dj_mooo]

sis pwd bang gamitin ung transfo ng microwave?

ang size po ng

center leg 27cm
ung EI nya e 86cm
taba ng transfo 62cm

secondary lng po tinanggal k...ung primary po hnd po

[xhunter]

Hi

Meron ako dito transformer Calculator, tables para sa wire conversion etc.. Lagi ko sya gamit every time gumagawa ako transformer..
Let me know kung gusto nyo copy.. upload ko sya.. 

sobra ang turn ng calculator na ito, sinubukan kong gumawa ng charger ung 14v naging 19 volts

ito ung ginagamit kong formula noong alaktrician pa ako


E=4.44βANf×10 to neg.8

E =  volt

β= 60,000

A = area of core (inner core)  square in

N = no. of turns

f  =  frequenzy (60hrtz)   
 
E  =  4.44βANf × 10 to power of neg. 8

N =E / 4.44βAf × 10 to power of neg. 8             or             N  =   E × 10to power of 8 /  4.44βAf